1. Field of the Invention
The present invention relates to the field of display technology, and in particular to a display device using a quantum dot film.
2. The Related Arts
With the continuous progress of the display technology, people are increasingly demanding higher quality of display. The color gamut that the liquid crystal television that are currently available in the market can display is in the range of 68%-72% NTSC (National Television Standards Committee), making it not possible to provide a high quality color effect.
Quantum dots (QDs) are semiconductor crystal particles having a particle size between 1-100 nm. The particle sizes of QDs are relatively small, smaller than or close to the exciton Bohr radius, and may cause the quantum confinement effect so that the continuous energy band structure of the base material may be converted into a separate energy band structure. Under the excitation of external energy, electrons may migrate and emit fluorescence.
Such a unique energy band separation structure of the QDs make the full width at half maximum thereof relatively narrow and may thus emit monochromic light having improved purity, providing a higher light emission efficiency than the conventional display devices. Also, since the energy band gaps of the QDs is greatly affected by the size thereof, it is possible to adjust the size of the QDs or use different ingredients of QDs to emit different wavelengths of light. To satisfy the needs of people for wide gamut and high color saturation, inclusion of electroluminescent QD devices in backlight modules is an effective solution for the major display manufacturers.
However, to use a QD material in backlighting, the excitation efficiency of QDs is always a practical issue of concerns. Directly using backlighting to excite QDs may readily lead to the problem of poor excitation efficiency.